1. Field Of The Invention
The present invention relates to an improved process for polymerizing 1-olefins and a titanium-containing catalyst therefor.
2. Description of the Prior Art
1-olefins have heretofore been polymerized in contact with catalyst systems comprised of titanium-containing compositions and cocatalysts or activators comprised of organic metallic halides and/or other compounds.
A variety of solid titanium halide-containing compounds have been developed and used heretofore for polymerizing and copolymerizing olefins. For example, U.S. Pat. No. 3,718,635 to Tomoshige et al. describes a pulverulent titanium catalyst obtained by copulverizing a low valency titanium halide compound and an organoaluminum compound. U.S. Pat. No. 4,028,481 to Shiomura et al. discloses a catalyst obtained by copulverizing a low valency titanium halide with an organic compound containing oxygen, sulfur or phosphorus. U.S. Pat. No. 4,659,792 to Kashiwa et al. discloses a titanium catalyst component prepared by reacting magnesium chloride, a titanium halide and a diester such as a diester of a dicarboxylic acid.
A titanium halide-containing compound which is particularly effective as a catalyst for polymerizing olefins is comprised of a TiCl.sub.3 complex prepared by reducing TiCl.sub.4 with an aluminum halide, treating the reduced solid with a complexing agent and then bringing the complexing agent treated solid into contact with additional TiCl.sub.4. A second catalyst component, i.e., an organic aluminum halide, which functions as an activator is utilized with the TiCl.sub.3 complex. Such a catalyst and its use in polymerizing 1-olefins is described in U.S. Pat. No. 4,210,738 to Hermans et al.
By the present invention, an improved process and two-component catalyst for polymerizing 1-olefins are provided which result in improved catalyst productivity and polymer properties.